Well "just shooting things" is also kinda what a militarily does, especially in wartime.
So, I don't think it's a "bad" thing to have BAF-GRN fights, and not even in Leeds. (what made BAF/KNF fights or LN-RM fights in 4.85 any more/less fun anyways?
If the problem is just simply "stagnation" as the OP suggests, then the simple solution IS storyline progression.
So, the real discussion is where the story goes that:
1. makes RP sense
2. generates activity and interest for all factions involved
Maybe let's have some events revolving around Leeds/Magellan fights (as opposed to the random ones we have been doing, and open to other factions like Colonials, Council, etc.). Maybe some TAU or Languedoc raids by BAF or BIS/LSF task forces? Maybe a "Dolittle Raid" not into Gamma, but into IDF or Burgundy? Maybe find an actual military use for all those military-grade jump drives?
All of these sound more interesting and fun and dignifying than a simple "Bretonia surrenders & becomes puppet state" scenario. I wouldn't be surprised if that's partly why Kusari activity and interest died.